unheard-of

adjective

un·heard-of ˌən-ˈhərd-ˌəv

-ˌäv

Synonyms of unheard-of

: previously unknown

especially : unprecedented

moving at unheard-of speeds

Examples of unheard-of in a Sentence

houses selling at unheard-of prices

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

An unheard-of benefit for this group of patients with this terrible disease. — Bryan C. Donohue, Baltimore Sun, 1 Sep. 2026 The band features an almost unheard-of 11 musicians, all among Ireland’s best in their musical specialties. — Dan Kelly august 30, Kansas City Star, 30 Aug. 2026 That is unheard-of with prolonged exposure, cognitive processing, and certainly SSRIs, the current standard-of-care options. — Anderson Cooper, CBS News, 16 Aug. 2026 To fix the problems at the factory, the company would team up with yet another unheard-of partner promising technological innovation. — Jesse Coburn, ProPublica, 12 Aug. 2026 See All Example Sentences for unheard-of

Word History

First Known Use

1592, in the meaning defined above

Time Traveler

The first known use of unheard-of was in 1592

See more words from the same year

Browse Nearby Words

unheard

unheard-of

unhearing

See all Nearby Words

Cite this Entry

Style

“Unheard-of.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unheard-of. Accessed 4 Sep. 2026.

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Kids Definition

unheard-of

adjective

un·heard-of

-ˌəv,

-ˌäv

: previously unknown : unprecedented

moving at unheard-of speeds

unheard-of

adjective

Synonyms of unheard-of

Examples of unheard-of in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Kids Definition

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